Oscillations reducing device



April 17, 1951 F. M. M. B. SALOMON OSCILLATIONS REDUCING DEVICE Original Filed May 14, 1940 2 Sheets-Sheet 1 MW m/ m i 1 WW N. j mm 0% April 17, 1951 F. M. M. B. SALOMON OSCILLATIONS REDUCING DEVICE Original Filed May 14, 1940 2 Shets-Sheet 2 Patented Apr. 17, 1951 v.OSCILLA'IION S REDUCING; DEVICE -Francoisf Marie Michel Bernard?salomflili'f'Paris, France; vested'in the Attorney'General of the United States Original .1applicationv May-1 4, 1940,, Serial No.

1 335,081. .Dividedami is his application May, 25,

.1945, Serial 'No. 595,839. In Luxembourg May This invention relates .to devices" forreducing oscillations, and vibrations in any structure, but more particularly" in machine shafts.

'This application is a divisionof my copending parent application Serial-No. 33 53081, filed May 14', 1940, for Oscillations Reduction Device, andany subject matter contained in said parent application which is applicable to the disclosure ofjthe present application, isincorporated herein by reference.

Thepresent inventionf is, applicable to ."the damping of torsional," fiexional and lateral oscillations.

The. devices, according' to the present invention, can be placed in any part .ofithe machine, and, particularly, on -.themachine shaft. 1' Forinstance, it may be placed.atftheirontor.atlthe rear of a crankshaft, in the crankshaft, in engine balance-weights, on ventilators or ventilator pulleys, in the arrangements of connecting rods, in propeller" hubs, 'on, aero 1sh'afts, .arid.on,marine shafts or the like. 7

The devices, according to'the present invention areidifierent from the centrifugal. pendulums heretofore usedv asv vibration 'dampers.

T Indeed, in the centrifugal, pendular systems the auxiliary centrifugal masses. are. submitted to'the' restoring force of the centrifugal? forces acting oni'themselves.

On'the contrary, ajde'vice, according toithe present invention,;c omprises at. least. one. member which is mountedlto rotate with valshaft and which rocks or oscillates underlthe. action of the disturbances. Said member is restored to its:'mean' 'position by at least one centrifugal restoring member carried by said oscillating member and operativelyconnected with? a part which is rotatively-movable'with" or; more-particularly; integral-with the shaft. The reaction of said part is the force *whichproduces-the restoration.

" In 1 devices" comprehended by the present invention 'the force which restores the oscillating member to its mean positionis due entirely or almost-entirely,- to the restoring forces resulting from the action" exerted by the restoring member carried by the oscillating memberg-whereasjdn the case of centrifugal pend'ulumsg the restoring' force is due to the actionof the-centrifugal forces; actingzon: the oscillating masses themselves.

The centrifugal; :resto'ring: member; acts= more particularly. as. arestoringlever,the.axis or. which is :carried bythe oscillating member; and restores the zlatterato .aitszmean' (position. bye being. operadisturbances.

tively connected with a member integral with the rotary shaft. In general the restoringmemher is effectivelya lever,--but-"the-samecanhlso act differently. The' oscillating member'can be centered orn'oton the axisof the shaft which creates the centrifugal forces and which-may or may-not be the shaft that is subjected to' the The oscillating member maybe'in theformof a--plate; a dis c,-cr a fractiorrof a disc or a flywheel. In-a'general way'it maybe cal-led a "harmon-icdisc, even-if properly spe'aking it is not -in-the shapeof-adisc. -As" has"already been-seenfiits working-is-entir'ely different from the working of centrifugal pendulums.

It has been-known--for'-atleast twenty- -five years that; in any: device intended for regularizingthe torques,--it-- may be advantageous to realize; more or' less exactly,-cert'ain' tuning conditions between the frequency or the disturbances and "thenatural "frequency-of the oscillating masses.

It is quite obvious-that theadvantage'of this tuning also existsyin generalyforthedevices embodying the presentinvention. The natural frequency-of the os'cillatingwei'ght member in said" devices-is the" one "which results' from the action" of the restoring member determined conditions. V

The connection'ybetween the'restoring member and" the corresponding oscillating-member can be" of any nature," such as cylindrical or spheric' articulations, cams; balls, ;or rollers.

According to the present invention, the-oscillating member preferably rocks or oscillates with little'cr very little friction; preferably; also,*-the restoring effects are-substantially-due-solelyto the'action of the-centrifugal' forces, '*without elastic means.

- However, it iswithin the scope of thepre'sent invention to employ frictional or elastio'means, fluid means and the like, either for the restoring of the oscillating mass or forany-other'reason.

' The" advantages of the devices-which the "invention' has'for' -''its object relative-to knoWn devices and especially to dampers utilizing eentrifugal pendulums are very consiEZer'abIe -for many difierent reasons. Those advantages may be substantially summedup as follows:

(a) They can be veryeeasily-sadaptedtor-"the elimination: of the lowest and highest harmonics. --(b) They: are more efiieient' than the known dampers, espe'ciallythose-withcentrifugal-pendw lums, under given.- conditions and for a 'given weight for the oscillating---members.

(0)" They 1 make 1 possible: the utilization of the 3 available space to the best advantage in the most simple manner.

(d) The conditions of resonance depend upon numerous and very different factors, which give great adaptability.

(e) For given conditions they are efficient at rotational speeds which are much lower than the lowest speeds at which known dampers are efficient.

(I) They avoid the use of noisy abutments and their working is always absolutely noiseless.

(9) They are of a very simple construction and of a very low cost.

(h) They afford in a very simple and efiicient manner the elimination of two or several harmonics simultaneously with only one oscillating member.

A construction embodying the present invention is diagrammatically illustrated, by way of example, in the accompanying drawings of which:

Fig. l is a side elevation of an embodiment of the invention wherein the oscillating member is eccentric with respect to the axis of the shaft;

Fig. 2 is a bottom view of the device illustrated in Fig. 1;

Fig. 3 is a section taken substantially on line C-D of Fig. 1;

Fig. 4 is a sectional view taken substantially on line AB of Figs. 2 and 3;

, Fig. 5 is a side elevation of the oscillating member shown in Figs. 1 to 4, inclusive;

' Fig. 6 is a sectional view taken on line T-U of Fig. 5; and,

Fig. '7 is a side elevation of one of the centrifugal members shown in Figs. 1 to 4, inclusive.

The drawings illustrate a device according to my invention mounted on the balance-weight of a machine shaft. Said machine could be, namely, an engine for any application, such as a radial or an in-line engine.

-In the illustrated embodiment, the shaft whereof the axis is O is integral with a web or arm 3| in which are bored two recesses 32 and 33 (Fig.4) fitted with rings 34 and 35 that are preferably made of tempered, cemented steel. Also, the ring 34 is preferably forced into the web 3|. The ring 35 can be loose.

. The oscillating member 36 is carried by restoring levers which restore it to its mean position when it moves away to the right or to the left under the action of disturbances. Said rocking mass 36 is constituted by two plates shown in Figs, 5 and 6 and connected by three stays forced into the plates, and preferably keyed on them, and consequently unable to turn relatively to them. One of these stays is constituted by the cylinder 31 (Fig. 6) and the other two by the cylinders 38 (Figs. 4 and 6). The nuts 37a, 31b, 38a and 381) complete the arrangement (Fig. 6).

The cylinder 31 (Fig. 6) extends through the recess 32 of the web 3| (Figs. 3 and 4) and is constantly lifted up by the restoring levers toward the axis 0 and under those conditions it constantly bears against the generatrix I of the ring 34 (Fig. 4) The two other stays 38 act as axes for the restoring levers 43 which are visible in Figs. 1 to 4, inclusive. One of said levers is shown separately in Fig. 7.

Each of the restoring levers 43 (Fig. 7) is constituted by a long plate having one extremity 44 thicker, as can be seen in Fig. 2. This increased thickness at the extremity tends to increase the distance between the center of gravity of the lever and its axis 38 carried by the oscillating member 36. This axis is constituted by one of the stays 38 (Figs. 2 and 6) and to insure the centering of the lever 43 on said axis, said lever is provided with a cylindrical hole 380 (Fig. 7) which could be fitted with a ring.

Additionally, the lever 43 is provided with a recess 58 (Fig. 7) fitted with a ring 42 and is further provided with a hole 39. The hole 39 of this lever permits the passage of the axis 38 for the second restoring lever which is placed symmetrically on the other side of the balance weight, as shown in Fig. 2. In effect, this figure shows that one of the restoring levers 43, the one at the bottom as viewed in the drawings, is articulated on the left cylindrical stay 38 while the restoring lever at the top in said figure is articulated on the right cylindrical stay 38. The hole 39 permits this last stay to pass. Likewise, the long holes 5| and 52 provided in the web 3| (Fig. 4) permit the passage of the two axes 38 when the member 36 rocks.

As to the recess (Fig. 7) the ring 42 transmits the restoring action to the rocking mass 36 through the roller 40, whereof the cheeks are numbered 4| (Fig. 3).

The operation is as follows: The mass 36 rocks about its mean position in a plane perpendicular to the axis of the shaft under the action of the disturbances and under the restoring action of the levers 43 of which, as it has been seen, the mass 36 carries the axes.

The action of levers 43 is as follows: Each of them under the action of centrifugal forces exerts a pressure on the roller 46 and through the said roller exerts a pressure on the wall of the recess 33, i. e., on the ring 35, carried'by the web 3|. Consequently, said web 3| exerts a reaction. This reaction of the web always tends to bring back to its mean position the structure constituted by the member 36 and the restoring levers 43 carried by the member 36.

The reactions due to the restoring levers give restoring torques which are added one to another and forces directed toward the axis 0 of the shaft which tend to move the mass 36 toward said axis. It results that the cylindrical stay 31 bears on the generatrix I (Fig. 4) with a force equal to the difference of this radial component due to the web and the centrifugal force exerted on the structure constituted by the member 36 and the restoring levers 43.

So, the oscillating member 36 rolls with direct rolling contact on the ring 34 to either side of the generatrix I.

Thus, the working is substantially the same as that in the case of the other embodiments disclosed in my above-mentioned parent application where the oscillating member is centered on the axis 0 of the rotary shaft the only difference being that the oscillation around the generatrix I (or around generatrices quite close to the generatrix I) replaces the oscillations around the axis 0. This operation is quite different from the operation of pendular systems.

The restoring torque thus obtained depends upon very varied factors, such as the positions and dimensions of the recesses, the relative values of the diameters of the rings and of the roller 4|], the weight of the rocking mass 36, the radius of gyration of said mass, the weights of the restoring levers, and the position of the center of gravity of each of the restoring levers.

As a different embodiment, the restoring levers can rest on the web 3| in the opposite direction, the reaction of this web tending on the contrary to ke'ep them'ovable structure away from the axis of the shaft I. .In thislcasenthe cylinder: Mirocks while rolling around the gen'eratrix J. at the bottom of the ring 34 (Eig. 4.),thelworking being substantially the same. This 'type of d'evice, wherein 'the restoring levers are-ipivotally mounted on the rotating shaft rather than bn the oscillating mass,- is fully disclosed in hiy co pendingapplic'ation Serial No. 333,561 ,llfi'led -it-is shown in Figs; l 'to 3 ofmy-above mentioned parent applicationgbr by any known process such as byusing ball, roller or needle bearin'gs 'or any rollin device.

'For theurpose-of'compensating' flexion'aror lat'eral oscillations;- similar devices can beused wherein theoscillating 'inemb'er rocks not in a plane perpendicular tothe a xi 'ofthe shaftbut in a plane of any orientation relatively to-said axis, namely, in a plane containing sa'd' axis. An example of such a 'structureis illustrate'din Figs. 9 and 10 f my above-mentioned prior filed copendingapplication Serial No} 3331561.

The-devices comprehended -by -the invention can,- in many casesgbetuned simultaneously-on two-or several harmonics. 'Ihe described devices could be varied without exceeding the scope of the invention Having now particularly de'scribed and ascertained the nature of my said invention-and-"in what manner the sameoper'ates, Ideclare that what I claim is:

1. In apparatHS fOr reducingmscillations in structures, a rotatable-member having a laterally extending portion provided witha curvedpath, an'oscillating member mounted on the rotatable member for angularmovementrelative thereto;a plurality of relatively-movable centrifugal restoring members pivotally mounted on said oscillating member, said restoring members having curved paths thereon," andforce transmitting means having engagement with and movable along each of the aforesaid *c'urved paths "for transmitting the restoringaction of saidcentrifugal members tosaid oscillating'memb'er.

2. -A-' vibration damper comprising in combination with a rotatable-memberhavinga laterally extending portion provided with an arcuatev path therein, an oscillatingmember formed of spaced rigidly connected elements mounted on said rotatable member for angular movement relative thereto, a pair of 'relativelvmovable centrifugal restoring'levers pivotally mounted on the os'c'llating member, said levers being provided with arcuate paths thereon,:and force-transmitting means having engagement with each of the aforementioned'a'rcuate paths foroperatively connecting the rotating member and said levers, the pivotal axes of said leversb'eing substantially diametrically disposed with respect to" said forceitr'ansmitting means.

3. In combination with a shaft having a laterally extending portion provided with an arcuate path, an oscillating member carried by said extending portion and angularly movable relative thereto, a pair of centrifugal members pivotally mounted on the oscillating member and having arcuate openings therein, and a roller having engagement with said arcuate path and said openings for operatively connecting the centrifugal members with the laterally extending portion,

with the arcuate 'means including means forces.

to said mean position from either thepenter' of gravity of eachmfithe centrifugal members being: spacedifromlthe' axis" of rotation of the shaft.

4. In a device for reducing vibrations 'in a structure having a rotating member provided with an arcuate path, an oscillating member mounted thereon and having angular movement relative thereto, a plurality'of relatively movable centrifugal restoring members mounted on the oscillating member for angular movement relative thereto, said restoring members/having arcuate paths therein, anda roller having rolling engagement pathsin the restoring members and the rotating member.

5. Ina device for reducing v'ibrations in an apparatus having a rotating member provided" with an arcuate path, anoscillating membermount'ed on the rotating -member and having' angul'ar movement relative theret0,'-' relatively movable centrifugal restoring members" pivotallymount'ed on the oscillating member for angular movement relative thereto, said restoringmembers having arcuate paths therein, and means having free rolling engagement-with the path in the rotating member and thepaths in the restoring members for transmitting forces between said rotating and restoring members.

6. In apparatus of the classdescribed, a'rotatable member, an oscillatable member adapted to be supported by said rotatable member and adapted for oscillatory'm'ovement' relative thereto about an axis eccentric to the axis of rotation oisaid rotatable member, centrifugally respon- 'sive'means mounted on said oscillatable member.

and means operatively connecting said'centr'ifugally responsive means and said rotatable member for 'moving said oscillatable" member to'a mean position.

'7. In apparatus for reducing'oscillations, r0- tatable means, Weightmeans adapted to be supported by said rotatable'm'eans and oscillatable relative thereto about an axis" eccentric to the axis of rotation of said "rotatable means, and means for resisting oscillation of said weight pivotally mounted on said weight means and responsive to *centr'ifugal 8. Apparatusfor reducing oscillations comprising rotatable means, weight means, and means operatively connecting said two first-named means whereby said weight means rotate with and are'adaptedfor limited oscillation relative to said rotatable means about an axis eccentric to the axis of rotation of said rotatable means, said connecting means including centrifugally responsive means-for restoring said'weightm'eans side thereof. 9.-Apparatus for reducing oscillations of a rotatable part comprising a damping mass, and

means operatively connecting said mass and .said

part whereby said mass is caused to rotate with "saidpart and is'ad'apted for limited oscillation relative to said partabout an axis spaced from the axis of rotation of said partysaidconnecting 'means being" constituted solely by rigid elements and including centrifugally responsive means for yieldably maintaining said damping mass in a predetermined mean position relative to said part during rotation of the latter.

10. Apparatus for reduicng oscillations of rotatable means comprising a damping mass, and means operatively connecting said mass and rotatable means whereby said mass is caused to rotate with said rotatable means and is adapted for limited oscillation relative to said rotatable means about an axis eccentric to the axis of rotation of 11. In a device for reducing vibrations in astructure having a rotating member, an oscillatable member mounted on the rotating member for oscillation about an axis eccentric to the axis of rotation of said rotating member, centrifugal restoring means mounted on the oscillatable member, and means operatively connecting said restoring means and rotating member for restoring the oscillatable member to a predetermined mean position relative to said rotating member.

12. In apparatus of the class described, rotatable means, weight means mounted for oscillatory movement relative to said rotatable means about an axis eccentric to the axis of rotation of said rotatable means, centrifugallyactuated means movably carried by one of said two firstnamed means, and means operatively connecting said centrifugally actuated means and the other of said two first-named means for rendering the centrifugal force of said centrifugally actuated means effective to yieldably resist movement of said weight means in either direction from a predetermined mean position relative to said rotatable means.

13. In apparatus of the class described, rotatable means, weight means mounted for oscillatory movement relative to said rotatable means about an axis spaced from the axis of rotation of said rotatable means, centrifugally actuated means movably carried by one of said two first-named means, and means operatively connecting said centrifugally actuated means and the other of said two first-named means for rendering the centrifugal force of said centriiugally actuated means effective to apply a continuous force tending to maintain said Weight means in a predetermined mean position relative to said rotatable means.

14. In apparatus of the class described, rotatable means, weight means mounted for limited linear and angular movement relative to said rotatable means, centrifugally actuated means movably carried by one of said two first-named means, and means operatively connecting said centrifugally responsive means and the other of said two first-named means for rendering the centrifugal force of said centrifugally actuated means effective to yieldably resist movement of said weight means from a predetermined mean position relative to said rotatable means.

15. In apparatus of the class described, rotatable means, weight means, each of said means having a curved surface, the curvature of said surfaces being appreciably different, and means for holding said surfaces in engagement durin rotation of said rotatable means including centrifugally actuated means movably carried by one of said two first-named means and operatively connected with the other of said two first-named means, the centrifugal force of said centrifugally actuated means being efiective to yieldably resist oscillatory movement of said weight means from a predetermined mean position relative to said rotatable means.

16. In apparatus of the class described, rotatable means, weight means having a curved surface thereon engageable with a curved surface of less curvature on said rotatable means, centrifugally actuated means movably carried by one of said two first-named means, and means operatively connecting said centrifugally actuated means and the other of said two first-named means for rendering the centrifugal force of said centrifugally actuated means effective to hold said surfaces in engagement with each other and to yieldably resist movement of said weight means from a predetermined mean position relative to said rotatable means.

17. A vibration damper for a rotatable shaft comprising a weight, means to suspend the weight off center relative to said shaft for oscillation of limited range, centrifugally actuated means, and lever means connecting said lastnamed means with said weight to bias the latter toward the shaft.

18. A vibration damper for rotatable systems comprising a rotatable support, an off center annular guide therein, a weight having suspension means movable within the guide, and means to bias the suspension means centripetally.

19. A vibration damper for a rotatable shaft comprising weight means suspended eccentrically to said shaft for rotation therewith and for limited angular and linear movement relative thereto, centrifugally actuated means, and means cooperating with said last-named means and said weight means to yieldably bias the weight means centripetally.

20. A vibration damper for a rotatable shaft comprising weight means suspended eccentrically to the axis of rotation of the shaft for rotation therewith and limited angular and radial movement relative thereto, and centrifugally actuated means tending normally to bias the weight means toward the shaft.

FRANQOIS MARIE MICHEL BERNARD SALOMON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

